NYT Cooking: This quick sausage dish is perfect for spring. The dark green chard adds freshness, while the rhubarb lends a citrus-like sour note that cuts through the richness of the sausages. If you don’t have any mustard seeds on hand, leave them out. While they do add a pleasant heat and gentle crunch, you won’t miss them if you didn’t know they were supposed to be there. Use any kind of sausage you like here: pork, duck, lamb or turkey all work well with the rhubarb and greens.